Fluid valve assembly including valve body with seal retention features

ABSTRACT

A fluid valve includes a valve body, and a valve plug disposed in the valve body. The valve body includes a base and a cylindrical sidewall that together define a valve plug chamber. The valve body includes valve ports. The valve plug is rotatable relative to the valve body about a rotational axis. The valve plug supports an annular seal in such a way that, a) for certain orientations of the valve plug with respect to the valve body, the seal abuts and inner surface of the sidewall and provides a fluid-tight seal between the valve plug and the valve body, and b) during rotation of the valve plug relative to the valve body, the seal is moved relative to the valve body along a circular path. At least one of the valve ports includes a guiding feature that guides the seal along the circular path.

BACKGROUND

A fluid valve assembly includes a rotary plug valve, a motor that isused to actuate the rotary plug valve and a gear set that connects themotor to the rotary plug valve. A rotary plug valve is a type of fluidvalve that may be used to control fluid flow and distribution throughfluid supply systems. For example, rotary plug valves may be used tocontrol the flow of coolant through a vehicle cooling system. The rotaryplug valve may include a valve body and a valve plug operativelyconnected to the valve body by an elastomeric valve seal. Someconventional rotary plug valves rely on the force from the compressionof the elastomeric seal or a spring, or both, between the valve body andplug for sealing of the valve. Various hard seal materials (for example,thermoplastic, ceramic or metal) have also been used and usually utilizea spring to supply the relatively high sealing force required of hardseals. This force must be sufficient to seal the valve when the pressuredifferential across the valve is at its greatest. Therefore, in someconventional fluid valve assemblies, the valve actuator is sized to beable to rotate the valve plug against this maximum pressuredifferential, even though the actual pressure differential may be muchless. In some cases, this force can also result in excessive wear of theseal and the valve body, and reduces operating life of the valve.

High torque may also be experienced due to manufacturing tolerances ofthe valve, and due to dimensional changes caused from a change in theoperating temperature. To allow for these tolerances, manufacturers mayprovide the fluid valve assembly with an over-sized actuator.

Based on the foregoing, there is a need for a rotary plug valve thatincludes a sealing configuration that overcomes the limitations in theart, including providing reduced torque within the valve while ensuringfluid-tight sealing when there is a pressure differential across thevalve, even when the pressure differential across the valve is at amaximum.

SUMMARY

In some aspects, a fluid valve includes a valve body, and a valve plugdisposed in the valve body so as to rotate relative to the valve bodyabout a rotational axis. The valve body includes a base and a sidewallthat protrudes from a peripheral edge of the base in a directionparallel to the rotational axis. The sidewall and the base define avalve plug chamber. The valve body includes valve ports, each valve portintersecting the sidewall at an opening. The valve plug supports anannular seal in such a way that, a) for certain orientations of thevalve plug with respect to the valve body, the seal abuts and innersurface of the sidewall and provides a fluid-tight seal between thevalve plug and the valve body, and b) during rotation of the valve plugrelative to the valve body, the seal is moved relative to the valve bodyalong a circular path. At least one of the valve ports includes aguiding feature that guides the seal along the circular path.

In some embodiments, the guiding feature comprises a rib that protrudesfrom an inner surface of at least one of the valve ports, the ribadjoining the opening and protruding in a direction that isperpendicular to the rotational axis.

In some embodiments, the guiding feature protrudes into the fluid pathdefined by the valve port.

In some embodiments, the sidewall has a circular shape when viewed in across section that is transverse to the rotational axis and passesthrough the guiding feature. The guiding feature includes a curvilinearseal-facing surface. In addition, at least a portion of the seal-facingsurface, when viewed in the cross section, is not coextensive with anarc that extends across the opening and is an extrapolation of thecircular shape.

In some embodiments, the guiding feature comprises a first rib thatterminates in a first rib terminal end, and a second rib that terminatesin a second rib terminal end. The first rib and the second rib extendtoward each other, and a gap exists between the first rib terminal endand the second rib terminal end.

In some embodiments, each valve port comprises a tube, an intersectionof the tube with the sidewall corresponds to the opening, the guidingfeature comprises a first rib and a second rib, and the first rib andthe second rib each protrude from an inner surface of the tube.

In some embodiments, the first rib and the second rib are aligned alonga diameter of the tube.

In some embodiments, the first rib and the second rib each include aguide surface that faces the seal, and a portion of the guide surface isacutely angled relative to a centerline of the tube.

In some embodiments, the first rib and the second rib each include aguide surface that faces the seal, the first rib and the second rib eachinclude a trailing surface that is opposed to the guide surface, and thetrailing surface of each rib is tapered in a direction parallel to acenterline of the tube.

In some embodiments, the first rib and the second rib each include aguide surface that faces the seal, the first rib and the second rib eachinclude a trailing surface that is opposed to the guide surface, and thefirst rib and the second rib each have a hydrofoil shape in that theguide surface is convexly rounded and the trailing surface is angled soas have a minimum thickness at locations furthest from the guidesurface.

In some embodiments, each valve port comprises a tube, and the guidingfeature is a rib that extends across a diameter of the tube.

In some embodiments, the sidewall has a first radius, the rib has aguiding surface that faces the seal, the guiding surface has a secondradius, and the second radius is less than the first radius.

A fluid valve assembly includes a rotary fluid valve, an actuator thatis used to actuate the fluid valve and a gear set that connects theactuator to the fluid valve. The rotary fluid valve includes a valvebody and a plug assembly that is rotatably supported in the valve body,and is configured to reduce the torque required to rotate the plugassembly, and minimize the number of seals required. The plug assemblyis operatively connected to the valve body by an elastomeric valve seal.The valve body defines a number of ports for the directing of fluid todifferent locations within a cooling system, and a cavity for a plugassembly. The plug assembly includes a plug having a closed portion thatblocks fluid flow and an open portion that allows fluid flow to travelfrom one port to another. The plug assembly can be rotated relative tothe valve body between different port positions to either selectivelyblock or open ports.

The rotary fluid valve has reduced torque requirements for rotationrelative to some conventional rotary fluid valves. Torque reduction inthe rotary fluid valve is realized by providing the valve seal thatutilizes the fluid pressure within the valve to facilitate sealing. Thedevice provides the necessary sealing forces when they are needed, e.g.,in a fully closed position, and reduces forces while the valve is movingbetween fully closed positions. This minimizes wear of the seal and thusimproves the useable lifetime of the valve. The reduced frictionresulting from the reduced force of the seal while the valve is movingalso reduces the amount of energy to move the valve.

Upon closure of a valve port in the rotary fluid valve, fluid pressurewithin the valve body expands or contracts the seal in a radialdirection depending on the pressure differential to provide afluid-tight seal between the seal and the valve plug. The fluid pressurewithin the valve body also provides a force in an axial direction toprovide a fluid-tight seal between the seal and the valve body. Aninitial bias force is applied by an elastic member (i.e., a spring), andthe elastic member provides sealing when there is a low fluid pressuredifferential across the seal.

The rotary fluid valve advantageously reduces the torque required torotate the plug assembly in the valve body, reducing wear of the sealand valve body and increasing the reliability and durability of therotary fluid valve. In addition, since the torque required to rotate theplug assembly is reduced, a smaller actuator motor may be used toposition the plug assembly within the valve body. A smaller actuatormotor is advantageous since it occupies less space, uses less energy andis lower in cost.

The fluid valve assembly includes the fluid valve that includes a singlevalve seal that is carried on the plug, whereby the number of requiredseals for the fluid valve is reduced as compared to some conventionalfluid valves. Since the number of required valve seals is reduced, thecost of the valve assembly is reduced and manufacture is simplified.

The plug includes an annular groove, and the seal is disposed in thegroove. When the valve plug assembly is oriented relative to the valvebody so that the seal surrounds a port, the seal is retained within thegroove because clearance between the plug and an inner surface of thevalve body is small relative to the size of the seal. However, when thevalve plug assembly is rotated relative to the valve body, the seal maypass over a port opening in the valve body. In this situation, a portionof the seal may slump into the opening. Upon continued rotation of thevalve plug assembly, the portion of the seal that has slumped into theopening may become pinched between an edge of the opening and the valveplug. To address this issue, the fluid valve may include features thatretain the seal in the groove, whereby pinching of the seal duringrotation of the valve plug can be avoided. For example, in someembodiments, the valve plug may include a retention ring disposed in thegroove to retain the seal. In other embodiments, the seal may includeretaining features that engage corresponding features provided on thegroove. In still other embodiments, the valve body may include guidingfeatures associated with the opening that prevent seal pinching duringrotation of the valve plug relative to the valve body.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a fluid valve assembly.

FIG. 2 is a cross-sectional view of the fluid valve assembly with theactuator cover removed and as seen along line 2-2.

FIG. 3 is an isolated view of the gear set that mechanically connectsthe motor to the plug.

FIG. 4 is a top perspective view of the valve body.

FIG. 5 is top perspective view of the plug assembly.

FIG. 6 is another top perspective view of the plug assembly of FIG. 5.

FIG. 7 is a bottom perspective view of the plug assembly of FIG. 5.

FIG. 8 is an exploded view of the plug assembly of FIG. 5.

FIG. 9 is an end view of the seal of FIG. 8.

FIG. 10 is a cross-sectional view of the fluid valve as seen along line10-10 of FIG. 1.

FIG. 11 is a cross sectional view of the fluid valve as seen along line11-11 of FIG. 1.

FIG. 12A is a cross-sectional view of a portion of the fluid valveshowing the seal in a contracted configuration. In the contractedconfiguration, the seal segregates the valve plug chamber into the firstchamber (represented using a first cross hatch), and the second chamber(represented using a second cross hatch).

FIG. 12B is a cross-sectional view of a portion of the fluid valveshowing the seal in the contracted configuration and illustrating theforces on the seal in the contracted configuration.

FIG. 13A is a cross-sectional view of a portion of the fluid valveshowing the seal in an expanded configuration. In the expandedconfiguration, the seal segregates the valve plug chamber into the firstchamber (represented using a first cross hatch), and the second chamber(represented using a second cross hatch).

FIG. 13B is a cross-sectional view of a portion of the fluid valveshowing the seal in the expanded configuration and illustrating theforces on the seal in the expanded configuration.

FIG. 14 is a cross-sectional view of a portion of the fluid valveshowing the seal in a neutral (e.g., at rest) configurationcorresponding to a common fluid pressure in the first fluid chamber andin the second fluid chamber.

FIG. 15 is a bottom perspective view of an alternative embodiment plugassembly.

FIG. 16 is an exploded view of the plug assembly of FIG. 15.

FIG. 17 is a cross-sectional view of the of the plug assembly of FIG. 15as seen along line 17-17 of FIG. 15.

FIG. 18 is a top perspective view of another alternative embodiment plugassembly.

FIG. 19 is a perspective view of an alternative embodiment seal.

FIG. 20 is an end view of the seal of FIG. 19.

FIG. 21 is an exploded view of the plug assembly of FIG. 18.

FIG. 22 is a top perspective view of another alternative embodiment plugassembly that employs the seal of FIG. 19.

FIG. 23 is a bottom perspective view of the plug assembly of FIG. 22.

FIG. 24 is a cross-sectional view of the plug assembly of FIG. 22 asseen along line 24-24 of FIG. 22.

FIG. 25 is an exploded view of the plug assembly of FIG. 22.

FIG. 26 is a bottom perspective view of another alternative embodimentplug assembly.

FIG. 27 is an exploded view of the plug assembly of FIG. 26.

FIG. 28 is a cross-sectional view of the plug assembly of FIG. 26 asseen along line 28-28 of FIG. 26.

FIG. 29 is a bottom perspective view of another alternative embodimentplug assembly.

FIG. 30 is an exploded view of the plug assembly of FIG. 29.

FIG. 31 is a cross-sectional view of the plug assembly of FIG. 29 asseen along line 31-31 of FIG. 29.

FIG. 32 is a bottom perspective view of another alternative embodimentplug assembly.

FIG. 33 is an exploded view of the plug assembly of FIG. 32.

FIG. 34 is a cross-sectional view of the plug assembly of FIG. 32 asseen along line 34-34 of FIG. 32.

FIG. 35 is a top perspective view of an alternative embodiment valvebody.

FIG. 36 is a cross-sectional view of the valve body of FIG. 35 as seenalong line 36-36 of FIG. 35.

FIG. 37 is a side view of a portion of the inner surface of the valvebody illustrating a valve port of FIG. 35.

FIG. 38 is a cross-sectional view of the plug assembly of FIG. 35 asseen along line 38-38 of FIG. 35.

FIG. 39 is a cross-sectional view of the valve body of FIG. 35 as seenalong line 39-39 of FIG. 35.

FIG. 40 is a top perspective view of another alternative embodimentvalve body.

FIG. 41 is a cross-sectional view of the valve body of FIG. 40 as seenalong line 41-41 of FIG. 40.

FIG. 42 is a side view of a portion of the inner surface of the valvebody illustrating a valve port of FIG. 40.

FIG. 43 is a cross-sectional view of the valve body of FIG. 40 as seenalong line 43-43 of FIG. 40.

FIG. 44 is a top perspective view of another alternative embodimentvalve body.

FIG. 45 is a cross-sectional view of the valve body of FIG. 44 as seenalong line 45-45 of FIG. 44.

FIG. 46 is a side view of a portion of the inner surface of the valvebody illustrating a valve port of FIG. 44.

FIG. 47 is a cross-sectional view of the valve body of FIG. 44 as seenalong line 47-47 of FIG. 44.

FIG. 48 is a top perspective view of an alternative embodiment valvebody.

FIG. 49 is a cross-sectional view of the valve body of FIG. 48 as seenalong line 49-49 of FIG. 48.

FIG. 50 is a side view of a portion of the inner surface of the valvebody illustrating a valve port of FIG. 48.

FIG. 51 is a cross-sectional view of the valve body of FIG. 48 as seenalong line 51-51 of FIG. 35.

FIG. 52 is a top perspective view of another alternative embodimentvalve body.

FIG. 53 is a cross-sectional view of the valve body of FIG. 52 as seenalong line 53-53 of FIG. 52.

FIG. 54 is a side view of a portion of the inner surface of the valvebody illustrating a valve port of FIG. 52.

FIG. 55 is a cross-sectional view of the valve body of FIG. 52 as seenalong line 55-55 of FIG. 52.

FIG. 56 is a top perspective view of another alternative embodimentvalve body.

FIG. 57 is a cross-sectional view of the valve body of FIG. 56 as seenalong line 57-57 of FIG. 56.

FIG. 58 is a side view of a portion of the inner surface of the valvebody illustrating a valve port of FIG. 56.

FIG. 59 is a cross-sectional view of the valve body of FIG. 56 as seenalong line 59-59 of FIG. 56.

DETAILED DESCRIPTION

Referring to FIGS. 1-4, a fluid valve assembly 1 includes a fluid valve2 and an actuator 200 that is used to actuate the fluid valve 2. Thefluid valve assembly 1 may be used for example, to control thedistribution and flow of coolant in a vehicle cooling system. The fluidvalve 2 is a rotary plug valve. The rotary plug valve 2 is mounted tothe actuator housing 202, and includes a plug assembly 60 that isdisposed in, and rotates relative to, a valve body 4 about a rotationalaxis 64. The valve body 4 includes three valve ports 24, 26, 28, and therotational orientation of the plug assembly 60 relative to the valvebody 4 is set via the actuator 200. The rotational orientation of theplug assembly 60 relative to the valve body 4 determines one or morefluid flow paths through corresponding ones of the valve ports 24, 26,28. The rotary plug valve 2 has a single, elastomeric valve seal 130that provides a fluid-tight seal between the valve body 4 and the plugassembly 60. The seal 130 is supported on a plug 62 of the plug assembly60, and utilizes the fluid pressure within the valve body 4 tofacilitate sealing between the valve body 4 and the plug 62. The valveseal 130 is implemented in such a way as to reduce torque requirementsfor plug rotation, as discussed in detail below.

References to direction made herein, such as up, down, upper, lower,top, bottom, front or rear are made with respect to the orientation offluid valve assembly as shown in FIG. 1. The references to direction arerelative and not intended to be limiting, and it is understood that thefluid valve assembly can be used in orientations other than theorientation shown in FIG. 1.

The actuator 200 includes the actuator housing 202, an electric motor220 that is disposed within the actuator housing 202, and a gear set 224that connects the motor 220 to the fluid valve 2. The gear set 224 isconfigured to reduce the rotational speed of the motor output shaft 222and to rotate the plug assembly 60 about a rotational axis 64. Theactuator housing 202 includes a shallow, tray-like container 302 and acover 340 that closes an open end of the container 302. The electricmotor 220, the gear set 224 and a printed circuit board 240 thatincludes a controller (not shown) are supported within the actuatorhousing 202, for example via stand-offs that project from both thecontainer 302 and the cover 340. Electrically conductive pins 242provide an electrical connection between the printed circuit board 240and an electrical connector 210 that protrudes outwardly from a sidewall306 of the container 302. In addition, a pair of electrically conductiveleads (not shown) connect the printed circuit board 240 to the motor220.

An output shaft of the gear set 224, e.g., the valve drive shaft 236,extends through an opening in a bottom 304 of the container 302, andinto the valve body 4, where it engages the plug 62 of the plug assembly60 as discussed further below. The valve drive shaft 236 is supported bya bushing 239 for rotation about the rotational axis 64. The opposedends of the bushing 239 are sealed with shaft seals 238. The bushing 239and seals 238 are disposed in a hollow boss 308 that protrudes inward,e.g., toward the cover 340, from the container bottom 304.

The rotary plug fluid valve 2 includes the valve body 4, and the plugassembly 60 that is disposed in, and rotates relative to, the valve body4. The valve body 4 includes a base 10, and a sidewall 8. The sidewall 8is joined at one end to a periphery of the base 10, and the sidewall 8surrounds the base 10. The sidewall 8 and the base 10 together form agenerally cup-shaped structure that defines a valve plug chamber 6therein. A free end 20 of the sidewall 8 (e.g., the end of the sidewall8 that is spaced apart from the base 10) abuts the outer surface of thecontainer bottom 304. The interface between sidewall 8 of the valve body4 and the outer surface of the container bottom 304 is sealed via anO-ring 322 that encircles the sidewall free end 20.

The valve body 4 includes a cylindrical stub 12 that protrudes from thebase 10 in a direction toward the actuator housing 202. The stub 12 iscentered on the base 10, and is co-axial with the rotational axis 64.The stub 12 is received in a cylindrical recess 78 provided in the plug62. The stub 12 centers the plug assembly 60 within the valve plugchamber 6, and the plug assembly 60 is driven to rotate on the stub 12about the rotational axis 64 via the valve drive shaft 236, as discussedfurther below.

The valve body 4 includes a stop 14 that protrudes from the base 10 in adirection toward the actuator housing 202. The stop 14 is locatedbetween the stub 12 and the sidewall 8, and has the shape of a generallyrectangular prism in which opposed lateral sides 15, 16 of the prism arealigned with a radius of the valve body 4. In certain rotationalorientations of the plug assembly 60 relative to the valve body 4, thestop 14 engages with a rib 72 that protrudes from an outer surface ofthe valve body 4, as discussed further below.

In the illustrated embodiment, the valve body 4 has three valve ports,including a first valve port 24, a second valve port 26 and a thirdvalve port 28. Each of the valve ports 24, 26, 28 includes a tube 30that protrudes outward from the sidewall 8, and communicates with thevalve plug chamber 6. Although a length of each valve port may differ,each valve port 24, 26, 28 has the same cross-sectional shape andcross-sectional dimension. In the illustrated embodiment, the tubes 30that form the valve ports 24, 26, 28 are cylindrical tubes, and eachvalve port 24, 26, 28 forms a circular opening 34 at the intersectionwith the valve body sidewall 8.

The valve ports 24, 26, 28, are provided at spaced-apart locations abouta circumference of the sidewall 8. In the illustrated embodiment, thefirst and second valve ports 24, 26 are co-axial with a first valve bodytransverse axis 32, and are positioned on diametrically opposed sides ofthe valve body 4. The third valve port 28 is co-axial with a secondvalve body transverse axis 36, where the second valve body transverseaxis 36 is perpendicular to the first valve body transverse axis 32. Asa result, the third valve port 28 is disposed mid-way between the firstand second valve ports 24, 26 along a circumference of the valve bodysidewall 8. The first and second valve body axes 32, 36 intersect therotational axis 64 and each other, and are perpendicular to therotational axis 64. As a result, the valve ports 24, 26, 28 reside in asingle plane that is perpendicular to the rotational axis 64 of the plugassembly 60.

Referring to FIGS. 5-11, the plug assembly 60 includes the plug 62, theseal 130 that is carried in a groove 106 provided in the plug 62, and anelastic member 160 that is disposed in the groove 106 and biases theseal 130 toward the valve body 4.

The plug 62 is a generally cylindrical member having a first end 66 thatfaces the actuator housing 202, and an opposed, second end 68 that isparallel to the first end 66 and faces an inner surface of the valvebody base 10. The plug 62 includes a side surface 70 that faces an innersurface of the valve body sidewall 8.

The first end 66 of the plug 62 includes a centrally-located firstrecess 74 that is configured to receive, and mechanically engage with,the valve drive shaft 236. Although the first recess 74 has an innersurface that is generally cylindrical, the recess inner surface includesa flat portion 76 that faces the rotational axis 64. When the plugassembly 60 is assembled with the valve drive shaft 236, an end of thevalve drive shaft 236 is disposed in the first recess 74, and a flatportion 235 provided on the valve drive shaft 236 abuts the first recessflat portion 76. When the valve drive shaft 236 is actuated by the motor220, the engagement between the respective flat portions 76, 235 allowsthe valve drive shaft 236 to rotate the plug 62 about the rotationalaxis 64.

The second end 68 of the plug 62 includes a centrally located secondrecess 78 that is configured to receive the stub 12. The second recess78 has a cylindrical inner surface that is dimensioned to receive thestub 12 in a clearance fit. The stub 12 serves as a spindle on which theplug 62 revolves.

The second end 68 of the plug 62 includes an elongated rib 72 thatprotrudes toward the valve body base 10. The rib 72 is a linearprotrusion that is aligned with a radius of the valve body 4. In certainrotational orientations of the plug assembly 60 relative to the valvebody 4, the rib 72 engages with the stop 14 provided on the base 10 ofthe valve body 4. The interaction between the rib 72 and the stop 14 mayprevent over-rotation of the plug assembly 60 relative to the valve body4. In addition, in some embodiments, certain control electronics (notshown) including, for example, a valve plug position sensor, may beinitialized by rotating the plug 62 relative to the valve body 4 untilthe rib 72 engages with the stop 14 while simultaneously using a sensorto detect the rotational orientation of the plug 62.

The plug 62 includes a linear first groove 84 that extends diametricallythrough the plug 62 in a direction perpendicular to the rotational axis64. The first groove 84 defines a “U” shape that opens at acircumference of the side surface 70 so that the first groove 84 opensfacing the valve body sidewall 8. The first groove 84 is co-axial with afirst plug transverse axis 86 that is perpendicular to, and intersects,the rotational axis 64. In some rotational orientations of the plugassembly 60 relative to the valve body 4, for example when the firstplug transverse axis 86 is parallel to the first valve body transverseaxis 32, the first groove 84 provides a portion of a fluid passage 88that extends between the first valve port 24 and the second valve port26.

The side surface 70 of the plug 62 is truncated on a side of the plug 62that is opposed to the first groove 84, whereby the side surface 70 hasa planar portion 80. The plug 62 includes a hollow, tubular protrusion94 that protrudes outward from the planar portion 80. The tubularprotrusion 94 is relatively thin-walled, and an inner surface of thetubular protrusion 94 defines a blind hole 100. The tubular protrusion94 is co-axial with a second plug transverse axis 90 that isperpendicular to, and intersects, both the first plug transverse axis 86and the rotational axis 64. The tubular protrusion 94 opens facing thevalve body sidewall 8, and a narrow gap g (FIG. 2) exists between aterminal end 98 of the tubular protrusion 94 and the valve body sidewall8. The gap g is dimensioned so that there is no interference between thetubular protrusion 94 and the valve body sidewall 8 during rotation ofthe plug 62, and to permit fluid flow to occur between the tubularprotrusion 94 and the valve body sidewall 8.

The tubular protrusion 94 has a cross-sectional shape and dimension thatcorresponds to the shape and dimension of the valve ports 24, 26, 28. Inthe illustrated embodiment, the valve ports 24, 26, 28 are cylindricaltubes 30. Thus, the tubular protrusion 94, and the blind hole 100 thatis defined by the inner surface of the tubular protrusion 94, arecylindrical in shape, and have a diameter that is equal to or greaterthan a diameter of the circular openings 34 in the valve body sidewall 8associated with the valve ports 24, 26, 28.

The plug 62 includes a sleeve 110 that surrounds the tubular protrusion94, is co-axial with the tubular protrusion 94 and is spaced apart fromthe tubular protrusion 94. Like the tubular protrusion 94, the sleeve110 has a cylindrical shape. The sleeve 110 and the tubular protrusion94 each have a non-uniform length lp to accommodate the cylindricalshape of the valve body inner surface 18, where the length lp of thesleeve 110 and the tubular protrusion 94 corresponds to a dimension in adirection parallel to the second transverse axis 90. In particular, thesleeve 110 and the tubular protrusion 94 each have a maximum length lp1at portions that are closest to the valve plug first and second ends 66,68, and a minimum length lp2 at portions that are disposed midwaybetween the valve plug first and second ends 66, 68.

The space between tubular protrusion 94 and the sleeve 110 defines anannular second groove 106 that surrounds the tubular protrusion 94. Thesecond groove 106 has a groove inner wall 108 that is shared with thetubular protrusion 94, and a groove outer wall 112 that is shared withthe sleeve 110. In addition, the second groove 106 has a groove blindend 114. Although in the illustrated embodiment, the groove blind end114 is a portion of the planar portion 80 of the valve plug side surface70, it is not limited to this configuration. The second groove 106receives the seal 130, and provides mechanical support for the seal 130during rotation of the plug assembly 60 relative to the valve body 4.

The annular seal 130 is disposed in the second groove 106. The seal 130has a seal outer surface 136 that faces the groove outer wall 112, and aseal inner surface 138 that faces the groove inner wall 108. The seal130 also has a first end 132 that faces the valve body sidewall 8, and asecond end 134 that is opposed to the first end 132 and faces the grooveblind end 114. The seal outer and inner surfaces 136, 138 may includesurface features that reduce dimensional tolerances necessary foreffective sealing, reduce friction between the seal 130 and the grooveinner and outer walls 108, 112, and mechanically support the seal 130during rotation of the plug 62 relative to the valve body 4. Forexample, in the illustrated embodiment, the seal outer surface 136includes an annular outer circumferential bead 140 (e.g., a bead) thatprotrudes outward and extends about an outer circumference of the seal130. In addition, the seal inner surface 138 includes an annular innercircumferential bead 146 (e.g., a bead) that protrudes inward andextends about an inner circumference of the seal 130.

The seal 130 has a non-uniform length ls to accommodate the cylindricalshape of the valve body inner surface 18, where the length ls of theseal 130 corresponds to a distance between the seal first and secondends 132, 134. In particular, the seal 130 has a maximum length ls1 atfirst portions 152 of the seal 130 that are closest to the valve plugfirst and second ends 66, 68 (e.g., at the top and bottom of the seal130 with respect to the orientation of the seal 130 shown in FIG. 8). Inaddition, the seal 130 has a minimum length ls2 at second portions 154of the seal 130, where the second portions 154 are disposed midwaybetween the first portions 152 (e.g., midway between the top and bottomof the seal 130 with respect to the orientation of the seal 130 shown inFIG. 8).

The seal first end 132 includes a first edge 142 that is located at anintersection of the seal first end 132 and the outer surface 136 of theseal 130, and a second edge 144 that is located at an intersection ofthe seal first end 132 and the inner surface 138 of the seal 130. Inaddition, the seal first end includes an annular concavity 156 that isrecessed relative to both the first edge 142 and the second edge 144. Asa result, the seal first end 132 has a shallow “V” shape that ensuresthat contact between the seal 130 and the valve body inner surface 18occurs at the outer and inner diameter of the seal 130. Advantageously,the shallow “V” shape also allows the seal to provide a surface wipingaction when the plug assembly 60 is rotated relative to the valve body4, preventing particles from getting between the seal first end 132 andthe valve body inner surface 18 that could cause damage. In someembodiments, the first and second edges 142, 144 “wear in” over time sothat the seal first end 132 eventually conforms to the shape of thevalve body inner surface 18.

The seal 130 is formed of an elastic material that is compatible withthe fluid that flows through the fluid valve 2 and meets therequirements for operating temperature and durability. For example, fora fluid valve used to control fluid in a vehicle coolant system, theseal 130 is formed of an elastomer that is compatible with automotivecoolant.

In some embodiments, the seal first end 132 may include a low-frictioncoating, whereby the seal first end 132 has a lower coefficient offriction than the remainder of the seal 130, including the seal outerand inner surfaces 136, 138 and the seal second end 134. In otherembodiments, the entirety of the seal 130 is coated with a coating thatis low friction relative to the elastomer used to form the seal 130. Inone non-limiting example, the seal 130 is formed of an elastomer, andthe coating is formed of a Polytetrafluoroethylene (PTFE). By providingthe seal 130 with a low-friction coating, the torque required to operatethe fluid valve 2 is reduced.

In some embodiments, as an alternative to a low friction coating, theseal 130 may include a “blooming” material. For example, the bloomingmaterial may be a wax that is incorporated in the seal 130 and thatseeps out of the seal 130 over time. In this example, the wax may coatthe seal 130 and serve as a lubricant that reduces friction.

The elastic member 160 is disposed in the second groove 106, so as toreside between the seal 130 and the second groove blind end 114. In theillustrated embodiment, the elastic member 160 is a spring such as acoil spring, a wave spring or a wave washer. The elastic member 160 maybe formed of stainless steel, but is not limited to this material. Theelastic member 160 provides a spring force Fs that is directed againstthe seal second end 134 in a direction parallel to the second plugtransverse axis 90. In other words, the elastic member 160 elasticallybiases the seal 130 toward, and against, the valve body inner surface18. The elastic member 160 enables the seal 130 to provide a fluid-tightsealing function under conditions when there is a low differentialpressure across the fluid valve 2, as discussed further below.

Referring to FIGS. 10-11, in use, the orientation of the plug assembly60 within the valve body 4 controls the fluid flow through the valveports 24, 26, 28. For example, in some operating conditions, the plugassembly 60 may be disposed in the valve body 4 in such a way that thefirst plug transverse axis 86 is aligned with the first valve bodytransverse axis 32. As a result, the first groove 84 is aligned with thefirst and second valve ports 24, 26 and provides a portion of the fluidpassage 88 that extends between the first and second valve ports 24, 26,whereby the first and second valve ports are open. In this orientation,the blind hole 100 is aligned with the third valve port 28. When theblind hole 100 is aligned with the third valve port 28, the seal 130surrounds the opening 34 associated with the third valve port 28, andforms a fluid-tight seal with both the valve body 4 and the plug 62. Asa result, the third valve port 28 is closed. In addition, the seal 130segregates the valve plug chamber 6 into a first chamber 38 thatgenerally borders an outer surface of the seal 130 and a second chamber40 that generally borders an inner surface of the seal 130. The seal 130provides a fluid-tight seal between the first chamber 38 and the secondchamber 40, which are discussed below with respect to FIGS. 12A and 13A.

The seal 130 utilizes the fluid pressure within the fluid valve 2 toprovide the fluid-tight seal between the valve plug 62 and the valvebody 4. In particular, the fluid-tight seal is achieved when there is apressure differential between the fluid in the first chamber 38 and thefluid in the second chamber 40. In addition, the borders of the firstchamber 38 and the second chamber 40 vary, and depend on valve operatingconditions including valve plug orientation and fluid pressuredifferentials, as discussed further below.

Referring to FIGS. 12A-14, there is a pressure differential across theseal 130 in certain valve operating conditions. When there is a pressuredifferential across the seal 130, the seal 130 is sufficiently elasticto radially expand or contract within the second groove 106 depending onthe pressure differential. During contraction of the seal 130 (FIGS. 12Aand 12B), the seal diameter decreases and the inner circumferential bead146 of the seal 130 forms a fluid-tight seal with the second grooveinner wall 108. During expansion of the seal 130 (FIGS. 13A and 13B),the seal diameter increases and the outer circumferential bead 140 ofthe seal 130 forms a fluid-tight seal with the second groove outer wall112.

During contraction of the seal 130, the seal inner circumferential bead146 segregates the valve plug chamber 6 into the first chamber 38 andthe second chamber 40 (FIG. 12A). In this case, the first chamber 38includes the volume defined by the fluid passage 88 and the gap g. Inaddition, the first chamber 38 includes the volume of the second groove106 defined between the seal inner circumferential bead 146, the sealouter surface 136, the second groove blind end 114 and the second grooveouter wall 112. The second chamber 40 includes the volume defined by theblind hole 100 and the volume of the second groove 106 defined betweenthe seal inner circumferential bead 146, the seal inner surface 138 andthe second groove inner wall 108.

During expansion of the seal 130, the seal outer circumferential bead140 segregates the valve plug chamber 6 into the first chamber 38 andthe second chamber 40 (FIG. 13A). In this case, the first chamber 38includes the fluid passage 88 and the gap g. In addition, the firstchamber 38 includes the volume of the second groove 106 defined betweenthe seal outer circumferential bead 140, the seal outer surface 136, andthe second groove outer wall 112. The second chamber 40 includes thevolume defined by the blind hole 100. In addition, the second chamber 40includes the volume of the second groove 106 defined between the sealouter circumferential bead 140, the seal inner surface 138, the secondgroove blind end 114 and the second groove inner wall 108.

When the plug assembly 60 is oriented relative to the valve body 4 sothat the fluid passage 88 is aligned with, and extends between, thefirst and second valve ports 24, 26, the first and second valve ports24, 26 are open and the third valve port 28 is closed. In thisconfiguration, the first chamber 38 has a higher pressure than thesecond chamber 40. When a fluid pressure in the first chamber 38 isgreater than the fluid pressure within the second chamber 40, therelatively higher pressure fluid that enters the second groove 106 fromthe first chamber 38 provides a fluid force Ff that is directed againstthe seal outer surface 136 in a direction perpendicular to, and toward,the second plug transverse axis 90. As a result of the inward fluidforce Ff, the seal 130 radially contracts so that the seal innercircumferential bead 146 contacts the groove inner wall 108 and forms afluid-tight seal with the groove inner wall 108 (FIG. 12B). At the sametime, the seal 130 is directed against the valve body 4 by the elasticmember 160 (Fs) and by the force of fluid that is present between theseal second end 134 and the second groove blind end 114 (Ff), where theforce of the fluid Ff against the seal second end 134 is greater thanthe spring force Fs against the seal second end 134. As a result, afluid-tight seal is provided between the seal first end 132 and thevalve body inner surface 18.

When a fluid pressure in the first chamber 38 is less than the fluidpressure within the second chamber 40, the relatively higher pressurefluid that enters the second groove 106 from the second chamber 40provides a fluid force Ff that is directed against the seal innersurface 138 in a direction perpendicular to, and away from, the secondplug transverse axis 90. As a result of the outward fluid force Ff, theseal 130 radially expands so that the seal outer circumferential bead140 contacts the groove outer wall 112 and forms a fluid-tight seal withthe groove outer wall 112 (FIG. 13B). At the same time, the seal 130 isdirected against the valve body 4 by the elastic member 160, and by theforce of fluid that is present between the seal second end 134 and thesecond groove blind end 114 (Ff), where the force of the fluid Ffagainst the seal second end 134 is greater than the spring force Fsagainst the seal second end 134. As a result, a fluid-tight seal isprovided between the seal first end 132 and the valve body inner surface18.

In use, a condition in which there is no pressure differential acrossthe fluid valve 2 occurs when the plug assembly 60 is in a partiallyopen position (FIG. 14). In the partially open position, the plugassembly 60 is oriented relative to the valve body 4 such that first andsecond plug transverse axes 86, 90 are not aligned with the first andsecond valve body transverse axes 32, 36 (e.g., are not aligned with thevalve ports 24, 26, 28). This occurs, for example, when the valve ports24, 26, 28 are transitioned between an open state and a closed state.

The seal 130 is dimensioned so that when the seal 130 is free ofexternal forces, the seal inner diameter d1 is greater than a diameterof the groove inner wall 108 (e.g., greater than a diameter of thetubular protrusion 94) and the seal outer diameter d2 is less than adiameter of the groove outer wall 112 (e.g., less than a diameter of thesleeve 110). As a result, when there is no pressure differential acrossthe fluid valve 2, the seal 130 generally floats within the secondgroove 106, and spacing may exist between the seal 130 and one or bothof the groove inner wall 108 and groove outer wall 112. In this state,elastic member 160 continues to direct the seal 130 against the valvebody inner surface 18 so that fluid is directed into the second groove106 and is present between the seal second end 134 and the second grooveblind end 114. The fluid that is present between the seal second end 134and the second groove blind end 114 may also contribute to directing theseal 130 against the valve body inner surface 18. As the plug assembly60 is rotated to an orientation in which the blind hole 100 is alignedwith one of the valve ports 24, 26, 28, a pressure differential acrossthe fluid valve 2 is developed and the fluid disposed in the secondgroove 106 facilitates formation of the fluid-tight seal, as describedabove with respect to FIGS. 12A-13B.

Referring to FIGS. 15-17, in some embodiments, the fluid valve 2 mayinclude an alternative embodiment plug assembly 460. The plug assembly460 illustrated in FIGS. 15-17 is similar to the plug assembly 60illustrated in FIGS. 1-14, and elements common to both embodiments arereferred to with common reference numbers. The plug assembly 460illustrated in FIGS. 15-17 differs from the earlier-described embodimentin that it includes a rigid retention ring 480 that is configured toretain the seal 130 in the second groove 106. The retention ring 480includes a first end 486 that faces the valve body sidewall 8, and anopposed second end 488 that faces the plug 462. The retention ring firstend 486 is angled relative to the second plug transverse axis 90 so asto form a continuous surface between valve body-facing ends of thetubular protrusion 94 and the seal 130. An outer surface 482 of theretention ring 480 has a tolerance fit with the seal inner surface 138.In addition, an inner surface 484 of the retention ring 480 is receivedin, and has an interference fit with, an annular cut out 490 provided inthe groove inner wall 108. The thickness of the retention ring 480 isgreater than the depth of the cut out 490, whereby the retention ring480 protrudes radially outward relative to the surface of the secondgroove inner wall 108. As a result, the retention ring second end 488may engage the seal inner circumferential bead 146 and limitdisplacement of the seal 130 toward the valve body inner surface 18.

Referring to FIGS. 18-21, in some embodiments, the fluid valve 2 mayinclude another alternative embodiment plug assembly 560 that includesan alternative embodiment plug 562, the elastic member 160 and analternative embodiment seal 530 that is carried in the second groove 106provided in the plug 562. The plug assembly 560 illustrated in FIGS.18-21 is similar to the plug assembly 60 illustrated in FIGS. 1-14, andelements common to both embodiments are referred to with commonreference numbers. The plug assembly 560 illustrated in FIGS. 18-21differs from the plug assembly 60 illustrated in FIGS. 1-14 in that theplug 562 and the seal 530 include features that serve to retain the seal530 within the second groove 106 of the plug 562. In particular, asurface (e.g., the outer wall 112) of the second groove 106 includesfirst retaining structures such as one or more latch-receiving throughopenings 566. In addition, the seal 530 includes second retainingstructure such as one or more protruding latches 532, where the numberof latches 532 provided on the seal 530 corresponds to the number ofthrough openings 566 provided in the second groove outer wall 112. Inthe illustrated embodiment, the plug assembly 560 includes four throughopenings 566 and four latches 532, but is not limited to this number ofretaining structures. The number of retaining structures may be fewer orgreater than four, and is determined by the requirements of the specificapplication.

The through openings 566 are elongated in a circumferential direction ofthe sleeve 510, and are spaced apart from each other along acircumference of the sleeve 510. In addition, the through openings 566are spaced apart from the planar portion 80 of the valve plug sidesurface 70. The sleeve 510 also includes a rectangular, key-receivingcut out 564 that is provided in the valve body-facing end 515 of thesleeve 510.

The seal 530 includes the latches 532 that protrude outward from theseal outer surface 136. The latches 532 are elongated in acircumferential direction of the seal 530, and are spaced apart fromeach other along a circumference of the seal 530. In addition, thelatches 532 are positioned on the seal outer surface 136 at the edgecorresponding to the seal second end 134. Each latch 532 has a beveledsurface 533 that faces the plug 562. The beveled surface 533 facilitatesinsertion of the seal 530 into the second groove 106 during assembly ofthe plug assembly. Each latch 532 has a normal surface 535 that isopposed to the beveled surface 533, and is perpendicular to the sealouter surface 136. In use, when the seal 530 is disposed in the secondgroove 106, the latches 532 protrude into the through openings 566 ofthe sleeve 510, and the normal surface 535 of each latch 532 engages anedge of the corresponding through opening 566. The engagement betweenthe latches 532 and the through openings 566 serves to retain the seal530 within the second groove 106, and to limit displacement of the seal530 toward the valve body inner surface 18.

The seal 530 includes a key 534 that protrudes outward from the sealouter surface 136. The key 534 has a shape that corresponds to the shapeof the key-receiving cut out 564. In the illustrated embodiment, the key534 has the shape of a rectangular prism. The key 534 is positioned onthe seal outer surface 136 at the edge corresponding to the seal secondend 134. In use, when the seal 530 is disposed in the second groove 106,the key 534 is received within key-receiving cut out 564 of the sleeve510. The engagement between the key 534 and the key-receiving cut out564 serves to properly orient the seal 530 relative to the second groove106 during assembly of the plug assembly.

The seal 530 illustrated in FIGS. 18-21 further differs from the seal130 illustrated in FIGS. 1-14 in that the seal 530 does not include theannular outer circumferential bead 140. During seal expansion, the sealouter surface 136 directly contacts, and forms a fluid-tight seal with,the second groove outer wall 112.

Referring to FIGS. 22-25, in some embodiments, the fluid valve 2 mayinclude another alternative embodiment plug assembly 660 that includesanother alternative embodiment plug 662, the elastic member 160 and theseal 530 of FIGS. 18-21. The plug assembly 660 includes elements commonto the previously described embodiments, and common elements arereferred to with common reference numbers. The plug assembly 660illustrated in FIGS. 22-25 differs from the previously described plugassemblies 60, 460, 560 in that the plug assembly 660 illustrated inFIGS. 22-25 includes two seals 530(1). 530(2), rather than the singleseal 130 provided in the previously-described plug assemblies 60, 460,560. The plug assembly 660 of FIGS. 22-25 is suitable for use, forexample, in a four port valve (not shown).

The plug 662 includes a hub 664 that supports the seals 530(1), 530(2)as discussed further below. The hub 664 includes a hollow stem 670 thatis coaxial with the rotational axis 64. The first end 672 of the stem670 includes a first recess 674 that is configured to receive, andmechanically engage with, the valve drive shaft 236. Although the firstrecess 674 has an inner surface that is generally cylindrical, therecess inner surface includes a flat portion 676 that faces therotational axis 64. When the plug assembly 660 is assembled with thevalve drive shaft 236, an end of the valve drive shaft 236 is disposedin the first recess 674, and the flat portion 235 provided on the valvedrive shaft 236 abuts the first recess flat portion 676. When the valvedrive shaft 236 is actuated by the motor 220, the engagement between therespective flat portions 676, 235 allows the valve drive shaft 236 torotate the plug 662 about the rotational axis 64.

The second end 673 of the stem 670 includes a centrally located secondrecess 678 that is configured to receive the stub 12. The second recess678 has a cylindrical inner surface that is dimensioned to receive thestub 12 in a clearance fit. The stub 12 serves as a spindle on which theplug 662 revolves.

The plug assembly 660 supports each seal 530(1), 530(2) as describedabove with respect to FIGS. 18-21. In particular, the seals 530(1),530(2) each cooperate with the corresponding tubular protrusion 94(1),94(2) and the sleeve 510 to provide valve sealing. The plug assembly 660differs from the plug assembly 560 described above with respect to FIGS.18-20 in that the tubular protrusions 94(1), 94(2) do not define blindholes 100, and instead each tubular protrusion 94(1), 94(2) defines aportion of a fluid passage 688 that passes through the plug 662.

In particular, the fluid passage 688 includes a first portion 690 and asecond portion 692. The first portion 690 is defined in part by thetubular protrusion 94(1) of the first seal 530(1), and the secondportion 692 is defined in part by the tubular protrusion 94(2) of thesecond seal 530(2). The first portion 690 intersects the second portion692 at the rotational axis 64. The first portion 690 is angled relativeto the second portion 692. For example, in the illustrated embodiment,the first portion 690 is perpendicular to the second portion 692, andboth the first and second portions 690, 692 are perpendicular to therotational axis 64.

The plug 662 illustrated in FIGS. 22-25 is similar to the plug 562illustrated in FIGS. 18-21 in that each seal 530(1), 530(2) of the plug662 includes features that serve to retain the seals 530(1), 530(2)within the second groove 106 of the plug 662. In particular, a surface(e.g., the outer wall 112) of the second groove 106 includes firstretaining structures such as one or more latch-receiving throughopenings 566. In addition, the seals 530(1), 530(2) include secondretaining structure such as one or more protruding latches 532.

The plug assembly 660 is useful in a two-port fluid valve (not shown) ora four-port fluid valve (not shown).

Referring to FIGS. 26-28, in some embodiments, the fluid valve 2 mayinclude an alternative embodiment plug assembly 760. The plug assembly760 illustrated in FIGS. 26-28 is similar to the plug assembly 460illustrated in FIGS. 15-17, and elements common to both embodiments arereferred to with common reference numbers. The plug assembly 760illustrated in FIGS. 26-28 is similar to the plug assembly 460illustrated in FIGS. 15-17 in that it includes a rigid retention ring780 that is configured to retain the seal 130 in the second groove 106.However, the retention ring 780 has a slightly different shape than theretention ring 480. In particular, the retention ring 780 includes afirst end 786 that faces the valve body sidewall 8, and an opposedsecond end 788 that faces the plug 462. The retention ring first end 786is flush with the valve body-facing end of the tubular protrusion 94. Inaddition, the retention ring first end 786 is perpendicular to secondplug transverse axis 90. Like the earlier-described retention ring 480,an outer surface 782 of the retention ring 780 has a tolerance fit withthe seal inner surface 138. In addition, an inner surface 784 of theretention ring 480 is received in, and has an interference fit with, anannular cut out 490 provided in the second groove inner wall 108. Thethickness of the retention ring 780 is greater than the depth of the cutout 490, whereby the retention ring 780 protrudes radially outwardrelative to the surface of the second groove inner wall 108. As aresult, the retention ring second end 788 may engage the seal innercircumferential bead 146 and limit displacement of the seal 130 towardthe valve body inner surface 18.

Referring to FIGS. 29-31, in some embodiments, the fluid valve 2 mayinclude an alternative embodiment plug assembly 860. The plug assembly860 illustrated in FIGS. 29-31 is similar to the plug assembly 460illustrated in FIGS. 15-17, and elements common to both embodiments arereferred to with common reference numbers. The plug assembly 860illustrated in FIGS. 29-31 is similar to the plug assembly 460illustrated in FIGS. 15-17 in that it includes a rigid retention ring880 that is configured to retain the seal 830 in the second groove 106.However, the plug assembly 860 illustrated in FIGS. 29-31 differs fromthe plug assembly 460 illustrated in FIGS. 15-17 in that it includes analternative embodiment seal 830, and in that the retention ring 880surrounds an outer surface 836 of the seal 830.

In the seal 830, the outer circumferential bead 146 is omitted, and theseal outer surface 836 includes an outwardly-protruding annular flange840. The flange 840 adjoins the seal second end 834. During sealexpansion, the flange 840 directly contacts, and forms a fluid-tightseal with, the second groove outer wall 112.

The retention ring 880 includes a first end 886 that faces the valvebody sidewall 8, and an opposed second end 888 that faces the plug 862.The retention ring first end 886 is flush with the valve body-facing endof the sleeve 110. In addition, the retention ring first end 886 isperpendicular to second plug transverse axis 90. An inner surface 884 ofthe retention ring 880 has a tolerance fit with the seal outer surface136. In addition, an outer surface 882 of the retention ring 880 isreceived in, and has an interference fit with, an annular cut out 890provided in the second groove outer wall 112. The thickness of theretention ring 880 is greater than the depth of the cut out 890, wherebythe retention ring 880 protrudes radially inward relative to the secondgroove outer surface 118. As a result, the retention ring second end 888may engage the flange 840 and limit displacement of the seal 130 towardthe valve body inner surface 18.

Referring to FIGS. 32-34, in some embodiments, the fluid valve 2 mayinclude an alternative embodiment plug assembly 960. The plug assembly960 illustrated in FIGS. 32-34 is similar to the plug assembly 860illustrated in FIGS. 29-31, and elements common to both embodiments arereferred to with common reference numbers. The plug assembly 960illustrated in FIGS. 32-34 is similar to the plug assembly 860illustrated in FIGS. 29-31 in that it includes the rigid retention ring880 that is configured to retain the seal 830 in the second groove 106and the seal 830. However, the plug assembly 960 illustrated in FIGS.32-34 differs from the plug assembly 860 illustrated in FIGS. 29-31 inthat it also includes the inner retention ring 780 as described abovewith respect to FIGS. 26-28. Thus, the seal 830 is retained in the plugassembly 960 by both the inner retention ring 780 and the outerretention ring 880.

Referring to FIGS. 35-39, in some embodiments, the fluid valve 2 mayinclude an alternative embodiment valve body 1004. The valve body 1004illustrated in FIGS. 35-39 is similar to the valve body 4 illustrated inFIGS. 1-14, and elements common to both embodiments are referred to withcommon reference numbers. The valve body 1004 illustrated in FIGS. 35-39differs from the valve body 4 illustrated in FIGS. 1-14 in that itincludes seal guiding features 1800 associated with the opening 34 ofeach port 24, 26, 28. The seal guiding features 1800 are configured toprevent seal pinching during rotation of the valve plug 62 relative tothe valve body 1004. That is, during rotation of the valve plug relativeto the valve body, the guiding features 1800 provide a ramped surface onwhich the seal rides, preventing the seal 130 from excessiveencroachment into the opening 34 while the seal is moved relative to thevalve body along a circular path having a radius that corresponds to theradius of curvature R1 of the valve body inner surface 18.

In the illustrated embodiment, the guiding features 1800 comprise a pairof opposed ribs 1802 that are disposed in the tube 30 of each valve port24, 26, 28. The ribs 1802 protrude from an inner surface 48 of the tube30 at a location adjoining the opening 34 in the sidewall 8 associatedwith each valve port 24, 26, 28. That is, the ribs 1802 protrude intothe fluid path defined by the valve port. The ribs 1802 protrude in adirection that is aligned with a diameter of the tube 30, and thus areperpendicular to the rotational axis 64. For the first and second valveports 24, 26, the ribs 1802 protrude in a direction that isperpendicular to the first valve body transverse axis 32. For the thirdvalve port 28, the ribs protrude in a direction that is perpendicular tothe second valve body transverse axis 36.

The ribs 1802 are identical to each other, extend toward each other, andare mirrored across the respective valve body transverse axis. For valveport 26, the ribs are mirrored across the first valve body transverseaxis 32. Each rib 1802 protrudes a distance lr1, and terminates in a ribterminal end 1804 that is spaced apart from the tube inner surface 48.The distance lr1 is less than a radius of the tube 30, whereby a gapexists between the respective terminal ends 1804 of the two ribs 1802that constitute the pair of ribs. In general the ribs 1802 havesufficient length to provide structure, and to simplify tooling andlimit flow resistance.

The ribs 1802 extend integrally from the inner surface of the tube 48,and rounded fillets are provided at the base 1805 of each rib 1802. Inthe embodiment illustrated in FIG. 37, the fillets have a radius R2.

Each rib 1802 includes a curvilinear seal-facing surface, referred to asa guide surface 1806, and an opposed trailing surface 1808. The seal 130slides along the guide surface 1806 during rotation of the valve plug 62relative to the valve body 1004. At least a portion of the guide surface1806, when viewed in the cross section, is not coextensive with an arc1810 that extends across the opening 34 and that is an extrapolation ofthe circular path (e.g., the arc 1810 has a radius R1).

In the illustrated embodiment, the guide surface 1806 has a curvilinearshape and a ramp portion 1814 of the guide surface 1806 is recessedrelative to the arc 1810. That is, the ramp portion 1814 resides withinthe tube 30. The ramp portion 1814 extends between a point α1 on theguide surface 1806 to a point β1 on the guide surface 1806. The point α1is the location at which the ramp portion 1814 intersects the ribterminal end 1804, and the point β1 is the location at which the rampportion 1814 intersects the radius R1 of the valve body sidewall innersurface 18. In this embodiment, the point β1 coincides with a point γ.The pointy corresponds to the edge of the port 26, e.g., the location atwhich a line that coextends with the tube inner surface 48 intersectsthe valve body inner surface 18 (e.g., intersects the arc 1810).

The ramp portion 1814 of the guide surface 1806 is at an acute angle θ1relative to a centerline of the tube 30, where the centerline of thetube 30 corresponds to the respective valve body transverse axis 32 or36. In the illustrated embodiment, the angle θ1 is about 62 degrees, butis not limited to this angle. For example, in some embodiments, theangle θ1 may be in a range of about 40 degrees to about 70 degrees.

The trailing surface 1808 of each rib 1802 is tapered in a directionparallel to a centerline of the tube 30, and is tapered in twoorthogonal directions. For example, as seen in a first cross sectionthat is transverse to the rotational axis 64 (FIG. 38), the rib terminalend 1804 has a dimension in a direction parallel to the tube centerlinethat is less than the corresponding dimension of the rib base 1805. As aresult, the trailing surface 1808 is angled relative to the tubecenterline. In another example, as seen in a second cross section thatis parallel to the rotational axis (FIG. 39), the ribs 1802 may have ahydrofoil shape in that the guide surface 1806 is convexly rounded andthe trailing surface 1808 is angled relative to the respective valvebody transverse axis 32 or 36 so as have a minimum thickness atlocations furthest from the guide surface 1806.

Referring to FIGS. 40-43, in some embodiments, the fluid valve 2 mayinclude another alternative embodiment valve body 2004. The valve body2004 illustrated in FIGS. 40-43 is similar to the valve body 1004illustrated in FIGS. 35-39, and elements common to both embodiments arereferred to with common reference numbers. The valve body 2004illustrated in FIG. 4043 is similar to the previous embodiment in thatthe valve body 2004 includes guiding features 1800 in the form of ribs2802. However, the ribs 2802 of FIGS. 40-43 differ in shape from theribs 1802 described above. In particular, the ramp portion 1814 of theribs 2802 extends between a point α2 on the guide surface 1806 to apoint β2 on the guide surface 1806. The point α2 is the location atwhich the ramp portion 1814 intersects the rib terminal end 1804, andthe point β2 is the location at which the ramp portion 1814 intersectsthe radius R1 of the valve body sidewall inner surface 18. In thisembodiment, the point β2 is inboard relative to the point γ, whichcorresponds to the edge of the port 26. In addition, the ramp portion1814 of the guide surface 1806 is at an acute angle θ2 relative to acenterline of the tube 30. In this embodiment, the angle θ2 is less thanthe angle θ1. For example, the angle θ2 may be about 49 degrees, but isnot limited to this angle.

In addition, the ribs 2802 have a length lr2 that is greater than thelength lr1 of the ribs 1802. The longer ribs 2802 have been found toprovide a more effective glide surface than that of the ribs 1802, buthave increased fluid pressure losses.

Although the valve body 2004 may include seal guiding features 1800 ineach port 24, 26, 28, the valve body 1004 is not limited to thisconfiguration. As seen in FIG. 41, the seal guiding features 1800 (i.e.,the ribs 2802) may be omitted from some ports. For example, in someembodiments, the ribs 2802 may be provided in only those ports that willbe closed, while an inlet port would not need to be closed and may befree of guiding features 1800.

Referring to FIGS. 44-47, in some embodiments, the fluid valve 2 mayinclude another alternative embodiment valve body 3004. The valve body3004 illustrated in FIGS. 44-47 is similar to the valve body 1004illustrated in FIGS. 35-39, and elements common to both embodiments arereferred to with common reference numbers. The valve body 3004illustrated in FIGS. 44-47 is similar to the previous embodiment in thatthe valve body 3004 includes guiding features 1800 in the form of ribs3802. However, the ribs 3802 of FIGS. 44-47 differ in shape from theribs 1802 described above. In particular, in the guide surface 1806 ofthe ribs 3802 includes the ramp portion 1814 that adjoins the ribterminal end 1804, and a protruding portion 1820 (e.g., a “bump”) 1820that is disposed between the ramp portion 1814 and the edge of the portγ. The bump 1820 protrudes beyond the arc 1810 and into the valve plugchamber 6.

Referring to FIGS. 48-51, in some embodiments, the fluid valve 2 mayinclude another alternative embodiment valve body 4004. The valve body4004 illustrated in FIGS. 48-51 is similar to the valve body 3004illustrated in FIGS. 44-47, and elements common to both embodiments arereferred to with common reference numbers. The valve body 4004illustrated in FIGS. 48-51 is similar to the previous embodiment in thatthe valve body 4004 includes a guiding features 1800 in the form of ribs4802. However, the ribs 4802 of FIGS. 48-51 differ in shape from theribs 3802 described with respect to FIGS. 44-47. In particular, in theribs 4802 have a fillet radius R3 that is less than the fillet radius R2of the ribs 3802, reducing fluid pressure loss through the port 26relative to earlier-described embodiments. However, the relativelygreater fillet radius R2 provides a wider rib 1802 at the edge of theport 26, and thus a larger surface area to distribute the load onto theseal 130. For example, the guide surface 1806 of the rib 1802 has agreater area A1 (FIG. 46) in the vicinity of the fillet having theradius R2 when compared to the guide surface 1806 of the rib 4802, whichhas an area A2 in the vicinity of the fillet having the radius R3.

Referring to FIGS. 52-55, in some embodiments, the fluid valve 2 mayinclude another alternative embodiment valve body 5004. The valve body5004 illustrated in FIGS. 52-55 is similar to the valve body 1004illustrated in FIGS. 35-39, and elements common to both embodiments arereferred to with common reference numbers. The valve body 5004illustrated in FIGS. 52-55 differs from the previous embodiment in thatthe valve body 5004 includes a guiding features 1800 in the form of asingle rib (e.g., a “rail”) 5802 that extends, uninterrupted, betweenopposed sides of the opening 34 along a diameter of the opening 34.

Although the rail 5802 provides increased flow resistance relative tothe ribs 1802 described in previous embodiments, the rail 5802 preventsthe seal 130 from being pinched between the valve plug assembly and thevalve body 5004 during rotation of the valve plug assembly with respectto the valve body 5004.

Each rail 5802 includes a curvilinear seal-facing surface, referred toas a guide surface 1806, and an opposed trailing surface 1808. The seal130 slides along the guide surface 1806 during rotation of the valveplug 62 relative to the valve body 1004. At least a portion of the guidesurface 1806, when viewed in the cross section, is not coextensive withthe arc 1810.

In the illustrated embodiment, the guide surface 1806 has a curvilinearshape and a ramp portion 1814 of the guide surface 1806 is recessedrelative to the arc 1810. That is, the ramp portion 1814 resides withinthe tube 30. The ramp portion 1814 extends between a point α3 on theguide surface 1806 to a point β3 on the guide surface 1806. The point α3is the location at which the ramp portion 1814 intersects a centralconcave portion 5804 of the guide surface 1806. The point β1 is thelocation at which the ramp portion 1814 intersects the radius R1 of thevalve body sidewall inner surface 18. In this embodiment, the point β1coincides with the point γ, whereby the ramp portion 1814 reaches thehousing radius at the edge of the port 26. The central concave portion5804 has a radius of curvature R4 that is less than the radius ofcurvature R1 of the valve body inner surface 18.

The ramp portion 1814 of the guide surface 1806 is at an acute angle θ3relative to a centerline of the tube 30, where the centerline of thetube 30 corresponds to the respective valve body transverse axis 32 or36. In the illustrated embodiment, the angle θ3 is about 61 degrees, andthus, it is relatively shallow. However, the angle θ3 is not limited tothis angle. For example, in some embodiments, the angle θ3 may be in arange of about 40 degrees to about 70 degrees.

The trailing surface 1808 of the rail 5802 is tapered in a directionparallel to a centerline of the tube 30. For example, the rail 5802 mayhave a hydrofoil shape in that the guide surface 1806 is convexlyrounded and the trailing surface 1808 is angled relative to therespective valve body transverse axis 32 or 90 so as have a minimumthickness at locations furthest from the guide surface 1806.

Referring to FIGS. 56-59, in some embodiments, the fluid valve 2 mayinclude another alternative embodiment valve body 6004. The valve body6004 illustrated in FIGS. 56-59 is similar to the valve body 1004illustrated in FIGS. 35-39, and elements common to both embodiments arereferred to with common reference numbers. The valve body 6004illustrated in FIGS. 56-59 is similar to the previous embodiment in thatthe valve body 6004 includes guiding features 1800 in the form of ribs6802. However, the ports 24, 26, 28 of the valve body 6004 includemultiple pairs 6801(a), 6801(b) of ribs 6802, where the rib pairs6801(a), 6801(b) are aligned along a direction parallel to therotational axis 64.

In the illustrated embodiment, the ports 24, 26, 28 of the valve body6004 include two pairs 6801(a), 6801(b) of ribs 6802, but are notlimited to two pairs 6801(a), 6801(b). The ribs 6802 of each rib pair6801(a), 6801(b) protrude from an inner surface 48 of the tube 30 at alocation adjoining the opening 34 in the sidewall 8 associated with eachvalve port 24, 26, 28. That is, the ribs 6802 protrude into the fluidpath defined by the valve port. The ribs 6802 protrude in a directionthat is perpendicular to the rotational axis 64 and is perpendicular tothe respective valve body transverse axis 32 or 36. The first rib pair6801(a) mirrors the second rib pair 6801(b) relative to a diameter ofthe tube 30.

The ribs 6802 may have a shape that corresponds to the features of anyof the previous rib embodiments, or various combinations thereof.Advantageously, using multiple rib pairs further distributes the load tothe seal 130, thus reducing the rate of wear of the seal 130 relative toembodiments having a single rib pair.

Although the plug assembly 60 is described herein as being disposed in athree-port valve body 4, it is understood that the any of the plugassemblies 60, 460, 560, 660 described herein may be used with analternative port body having a different number of ports, as required bythe specific application. Moreover, a given fluid valve 2 can performdifferent functions, depending on the configuration of the ports in thefluid system. Examples of various fluid valve configurations are nowprovided:

A three-port valve may have one of the following configurations:

One inlet, two outlet valve, where the valve seal seals both the inletand the outlets. In this case, the annular outer and innercircumferential beads 140, 146 extend over the full 360 degrees ofcircumference on the seal outer and inner surfaces 136, 138.

One inlet, two outlet valve, where the valve seal seals only theoutlets. In this case, only the annular inner circumferential bead 146is needed, and the seal outer surface 136 may have additional retentionfeatures.

Two inlet, one outlet valve, where the valve seal seals both the inletand the outlets. In this case, the annular outer and innercircumferential beads 140, 146 extend over the full 360 degrees ofcircumference on the seal outer and inner surfaces 136, 138.

Two inlet, one outlet valve, where the valve seal seals only the inlets.In this case, only the annular outer circumferential bead 140 is needed.

A four-port valve may have the following configuration:

Two inlet, two outlet valve, where the valve seal seals when thepressure differential is both positive and negative. In this case, theannular outer and inner circumferential beads 140, 146 extend over thefull 360 degrees of circumference on the seal outer and inner surfaces136, 138.

A five-port valve may also be provided which combines the functions ofthe three-port and four-port valves. It is contemplated that thefive-port valve may require the annular outer and inner circumferentialbeads 140, 146 which extend over the full 360 degrees of circumferenceon the seal outer and inner surfaces 136, 138.

The invention provides the necessary sealing forces when they areneeded, in a fully closed position, and reduces forces while the valveis moving between fully closed positions. This minimizes wear of theseal and thus improves the useable lifetime of the valve. The reducedfriction resulting from the reduced force of the seal while the valve ismoving also reduces the amount of energy to move the valve.

Although the valve ports 24, 26, 28 and the valve plug tubularprotrusion 94 are described herein as being cylindrical in shape, thevalve ports 24, 26, 28 and the valve plug tubular protrusion 94 may havealternative shapes as required by the specific application. For example,in some embodiments, valve ports 24, 26, 28 and the valve plug tubularprotrusion 94 may be rectangular tubes, or tubes having an irregularcross-sectional shape.

Although each valve port 24, 26, 28 is described herein as having thesame cross-sectional shape and cross-sectional dimension, the valveports 24, 26, 28 are not limited to this configuration. For example, insome embodiments, one or more of the valve ports may have a unique shapeand/or cross-sectional dimension.

In other embodiments, the radial fit between the seal and the groove isbiased in situations where the flow through the valve is only in onedirection. This bias allows for greater tolerances for the width of thegroove and seal allowing for easier manufacture.

In other embodiments, the valve plug may have a different valve pluggeometry that does not close off a valve port, but rather directs thefluid flow to different valve ports, depending on valve plug position.

In other embodiments, the elastic member and seal ll may be carried in agroove provided in the valve body rather than in the valve plug.

In other embodiments, the valve body may have a different number ofvalve ports, for example, ranging from two valve ports to five valveports.

In the embodiments illustrated in FIGS. 18-25, the plug assembliesinclude retaining structures. In particular, the outer wall 112 of thesecond groove 106 includes first retaining structures such as one ormore latch-receiving through openings 566, and the seal 130 includessecond retaining structure such as one or more protruding latches 532.It is understood that the retaining structures are not limited to thisconfiguration. For example, in some embodiments, the first retainingstructures may include latches formed on the groove outer wall 112, andthe second retaining structures may include recesses in the seal outersurface 136. In another example, the first and second retainingstructures may include structures that permit a bayonet, screw thread orother type of interlocking connection between the seal 130 and thesecond groove 106.

Selective illustrative embodiments of the fluid valve including thevalve body and plug assembly are described above in some detail. Itshould be understood that only structures considered necessary forclarifying the fluid valve have been described herein. Otherconventional structures, and those of ancillary and auxiliary componentsof the fluid valve, are assumed to be known and understood by thoseskilled in the art. Moreover, while working examples of the fluid valvehave been described above, the fluid valve is not limited to the workingexamples described above, but various design alterations may be carriedout without departing from the fluid valve as set forth in the claims.

What is claimed is:
 1. A fluid valve comprising a valve body and a valveplug disposed in the valve body so as to rotate relative to the valvebody about a rotational axis, wherein the valve body includes: a base; asidewall that protrudes from a peripheral edge of the base in adirection parallel to the rotational axis, the sidewall and the basedefining a valve plug chamber; and valve ports, each valve portintersecting the sidewall at an opening, the valve plug supports anannular seal in such a way that, a) for certain orientations of thevalve plug with respect to the valve body, the seal abuts an innersurface of the sidewall and provides a fluid-tight seal between thevalve plug and the valve body, and b) during rotation of the valve plugrelative to the valve body, the seal is moved relative to the valve bodyalong a circular path, at least one of the valve ports includes aguiding feature that guides the seal along the circular path.
 2. Thefluid valve of claim 1, wherein the guiding feature comprises a rib thatprotrudes from an inner surface of at least one of the valve ports, therib adjoining the opening and protruding in a direction that isperpendicular to the rotational axis.
 3. The fluid valve of claim 1,wherein the guiding feature protrudes into the fluid path defined by thevalve port.
 4. The fluid valve of claim 3, wherein the sidewall has acircular shape when viewed in a cross section that is transverse to therotational axis and passes through the guiding feature, the guidingfeature includes a curvilinear seal-facing surface, and at least aportion of the seal-facing surface, when viewed in the cross section, isnot coextensive with an are that extends across the opening and is anextrapolation of the circular shape.
 5. The fluid valve of claim 1,wherein the guiding feature comprises a first rib that terminates in afirst rib terminal end, and a second rib that terminates in a second ribterminal end, the first rib and the second rib extend toward each other,and a gap exists between the first rib terminal end and the second ribterminal end.
 6. The fluid valve of claim 1, wherein each valve portcomprises a tube, an intersection of the tube with the sidewallcorresponds to the opening, the guiding feature comprises a first riband a second rib, and the first rib and the second rib each protrudefrom an inner surface of the tube.
 7. The fluid valve of claim 6,wherein the first rib and the second rib are aligned along a diameter ofthe tube.
 8. The fluid valve of claim 6, wherein the first rib and thesecond rib each include a guide surface that faces the seal, and aportion of the guide surface is acutely angled relative to a centerlineof the tube.
 9. The fluid valve of claim 6, wherein the first rib andthe second rib each include a guide surface that faces the seal, thefirst rib and the second rib each include a trailing surface that isopposed to the guide surface, and the trailing surface of each rib istapered in a direction parallel to a centerline of the tube.
 10. Thefluid valve of claim 6, wherein the first rib and the second rib eachinclude a guide surface that faces the seal, the first rib and thesecond rib each include a trailing surface that is opposed to the guidesurface, and the first rib and the second rib each have a hydrofoilshape in that the guide surface is convexly rounded and the trailingsurface is angled so as have a minimum thickness at locations furthestfrom the guide surface.
 11. The fluid valve of claim 1, wherein eachvalve port comprises a tube, and the guiding feature is a rib thatextends across a diameter of the tube.
 12. The fluid valve of claim 11,wherein the sidewall has a first radius, the rib has a guiding surfacethat faces the seal, the guiding surface has a second radius, and thesecond radius is less than the first radius.